It is well known that animals and plants alike must maintain certain fluid levels or risk danger of dehydration. For animals including human beings, dehydration results in depriving bodily organs of vitality. Severe dehydration can result in damage to bodily organs or even death. When bodily fluid levels become low, the brain instinctively triggers a sensation of thirst. Drinking liquids such as water quenches thirst and, therefore, a body instinctively avoids becoming dehydrated. Today, numerous physical activities of human beings such as manual labor, jogging, hiking and bicycling causes the body to perspire, thus draining the body of bodily fluids. Again, the brain triggers a sensation of thirst to signal the need to replenish exhausted bodily fluids. Often, those engaged in physical activities have immediate access to sources of water or other liquids. These sources of water can be either fixed sources, such as water taps or water fountains, or portable sources of water such as a canteen or water bottle.
Today, a popular source of portable water is a plastic water bottle. Typically, these plastic water bottles are of single-wall construction and have a stem valve assembly mounted to a cap structure. Upon opening the stem valve, water can be squeezed from the plastic bottle and into a person's mouth for drinking. Unfortunately, those engaged in physical activities are usually outdoors during sunny daytime hours. Warm outdoor temperatures and direct sunlight tend to warm the water inside the plastic water bottle. Although warm water is adequate to quench a body's need for fluid, warm water is often unsavory to the drinker.
Insulated containers are well known in the art. One example of an insulated container is shown in U.S. Pat. No. 2,643,021 issued on Jun. 23, 1953 to Friedman and another example is shown in U.S. Pat. No. 3,164,148 issued Jan. 5, 1965 to Tolciss. Although both of these insulated containers would be effective in thermally insulating a liquid contained therein, such containers are not conducive for carrying by physical fitness enthusiasts.
An insulated container which is conducive for carrying by physical fitness enthusiasts and manual laborers is shown in my patent application, Ser. No. 07/645,569 filed Jan. 24, 1991 and entitled BOTTLE WITH REFLECTIVE BARRIER LAYER FOR REDUCING ELECTROMAGNETIC ENERGY TRANSFER, now U.S. Pat. No. 5,316,193. Generally, this insulated container, which is fabricated from a stiff yet resilient material, includes an inner container body having a continuous channel extending circumferentially about an inner cylindrical wall and an outer shell having a continuous rib projecting from and extending circumferentially around an outer cylindrical wall. The outer shell is sized and adapted to slidably receive the inner container body so that when the inner container body is disposed within the outer shell, the continuous channel of the inner container body matably engages with the continuous rib. This matable engagement retains the inner cylindrical wall and the outer cylindrical wall in a close-fitted yet spaced-apart relationship from each other to form void space therebetween. Also, the insulated container includes an insulating layer of metallic foil material which is disposed between the inner container body and the outer shell to shield against radiant energy of sunlight.
Although this insulated container is lightweight and effectively insulates liquids contained therein, there is a problem associated with its assembly. The circumferential rib projecting from the outer cylindrical wall constricts the interior of the outer shell. By design, the diameter of the inner container body is larger than the diameter of the constricted portion in the interior of the outer shell. It is, therefore, difficult to insert the inner container body into the outer shell at least until the continuous channel of the inner container body matably engages with the continuous rib of the outer shell. Furthermore, when the inner container body is enveloped with an insulating layer of metallic foil and is then inserted into the outer shell, occasionally, the insulating layer tears where the rib compresses the insulating layer onto the inner container body.
A need exists to provide an insulated water bottle to maintain a cool liquid temperature so that the user can drink a refreshing amount of liquid when desired. There is also a need to provide an insulated container which is lightweight and simple to manufacture and assemble. The present invention satisfies these needs.